Water well and water softener systems use pressurized water in pipes or other elements that are sometimes exposed to cold temperatures. Freeze protection in the past has typically utilized wrapping exposed elements with electrical heat tape or insulation or a combination of both methods. While these solutions are often satisfactory for most conditions, there exists a need for a non-electrical, non-passive system that engages pressurized elements of water supply assemblies for actively preventing freeze-up by temperature, with the use of the pressurized systems water, to purge the chilled water and subsequently, and as a direct result of purging, replace with warmer water. This action prevents the devices from freezing. There is also the need for flow control in water systems wherein water cooler than ambient is needed downstream of a water supply.